The invention relates to a method and a corresponding device for the registration of two 3D image data sets of an object to be imaged which is provided with a plurality of markers which are contained in the 3D image data sets. The invention also relates to an imaging device for the acquisition of medical 3D image data sets of an object to be imaged as well as to a computer program product.
Notably in the medical field it is often necessary to combine two or more 3D image data sets of the same object to be imaged, for example, a part of a patient, with adequate accuracy. Such 3D image data sets may be formed by means of the same or different imaging modalities, for example, X-ray techniques, computed tomography, an ultrasound technique or magnetic resonance tomography; moreover, the 3D image data sets may have been acquired at more or less large intervals in time.
In order to carry out the desired combination of the 3D image data sets it is necessary to realize so-called registration where the spatial relationship of the two 3D image data sets is determined and a transformation rule is defined in order to transform one of the two 3D image data sets to the co-ordinate system of the respective other 3D image data set. To this end, artificial or anatomical markers are often used so as to determine the spatial relationship of the 3D image data sets relative to one another.
A method of this kind is known from “Automated registration of multimodal brain image sets using computer vision methods”, G. Secretta, P. Gregson, Computers in biology and medicine 29 (1999), pp. 333 to 359. A frame which comprises two triangles on which markers which can be imaged are provided is then fitted to the head of a patient. The positions of the triangles are determined on the basis of the imaged markers by means of computer image processing, after which the transformation rule for the transformation of a 3D image data set to the co-ordinate system of the other 3D image data set is derived from said positions by means of quaternion mathematics.